Value-added services have become an integral part of a consumer's expectations regarding the consumer's mobile communications device. Many of these value-added services are emerging applications in Intelligent Networks (IN) for mobile applications and may include such services as video or music download services, automate call forwarding services, ring-back tone services, prepaid services, and the like.
In the Global System for Mobile Communications (GSM) network or Universal Mobile Telecommunications System (UMTS) network, the Customized Application of Mobile Enhanced Logic (Camel) standard has been developed to aid GSM operators to offer operator-specific services to their subscribers. The Camel protocol is defined in a set of standards established by the ETSI (European Telecommunication Standardization Institute) and later upgraded as part of 3GPP (Third Generation Partnership Project) initiative. They allow an operator to define services over and above standard GSM/UMTS services.
The services supported by Camel may include call processing functions such as caller ID and call screening, call forwarding, call rerouting, and the like. Prepay and Account Spending Limit (ASL) may utilize Camel to allow for metering usage on a prepaid basis and post-paid basis. Camel may allow for call control, information to be passed to databases, call assistance for routing to a Public Safety Answer Point, and query of location based infrastructures such as the Gateway Mobile Location Center for precise positioning of the mobile device. Other LBS applications emerging that rely on Camel include directory services and location-based search and information. Many services can be created using Camel, and it is particularly effective in allowing these services to be offered when a subscriber is roaming, like for instance no-prefix dialing.
GMS/UMTS networks typically provide a service that allows a restricting entity to have control over the handsets. For example, parents may wish to set usage limits on a child's talk time, text messages, instant messages, and downloads, manage how and when a child can communicate, block numbers they deem inappropriate and filter access to accessible content, restrict access to mobile Web sites, allocate minutes among users of shared wireless plans, and the like. A subscriber, such as the child, may dial an emergency number, such as 911, even if the restrictions in effect would not have allowed any other call. When a subscriber dials emergency call center numbers, by standard the call does not trigger Camel into the call because of the complexity added to the emergency call by the Camel protocol.
It would be desirable to lift the call restrictions that are in place under certain circumstances. For example, while the child may be authorized to make the call to an emergency or public safety call center, the call center is subject to restriction and can be blocked from contacting the child. So, if a child's connection to a 911 call center is dropped due to a faded signal, for example, the 911 call center may be restricted from calling the child back because the child has reached his or her quota of incoming calls for the month or the call took place at a time of the day when the child is not allowed to receive any incoming call.